A:Answer No, not quite.
What you describe is called 'Bluetooth Multipoint'. The Jaybird X2's let you pair up to 8 devices, but only 1 can be connected at a time.
Multipoint has been available for years, consumers have come to expect it -- especially in a $200 (after tax) headphone that went to market in 2015. The only reason I can think of why Jaybird left it out the X2's would be battery life. Multipoint would considerably reduce the 8-hours they've been rated for.